Spring suspension device



May 13, 1930. G. R. HOWEY SPRING SUSPENSION DEVICE Filed Nov. 15, 1927 Patented May 13, 1930 UNITED STATES PATENT OFFICE GEORGE R. HOWEY, OF BARBERTON, OHIO, ASSIGNOR TO THE B. F. GOODRICH COM- PANY, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK SPRING SUSPENSION DEVICE Application filed November 15, 1927. Serial No. 233,398.

This invention relates to suspension devices having a spring or springs therein for cushioning the suspension load or to permit their ready engagement with articles at a determinate distance below their support, an example being the suspension-hook device for handling tire-vulcanizing molds which is chosen for purposes of illustration herein.

Heretofore such devices as used in this association have usually consisted of a cylindrical casing containing a compression spring, a hook havingits shank secured to one end of the casing and a spring yoke extending through the spring and through an apertured guide cap on the other end of the casing, the

0 durable suspension device.

yoke being limited in its range of movement by projections thereon extending into closedended slots formed in the wall of the casing.

These devices of the prior art have been relatively heavy and expensive to manufacture, have been subject to frequent splitting of the casing by the force of the load drawing the stop-projections of the yoke strongly r against the end walls of the slots in the cas- 0 ing, and have required a great deal of labor for their repair or the replacement of parts.

The chief objects of my invention are to overcome these several disadvantages and especially to provide an inexpensive, light and Of the accompanying drawings Fig. 1 is a fragmentary elevation of a mold conveyor, a tire-mold assembly thereon, an undulating overhead track, and a suspension device mounted on the track and adapted to lift and transport the upper mold member of the tire-mold assembly, the suspension device being a preferred embodiment of my invention.

Fig. 2 is an elevation on a larger scale, with parts sectioned and broken away, of one of the members of the suspension device.

Fig. 3 is a section on line 33 of Fig. 2.

Referring to the drawings, a tire-mold conveyor is shown at 10 with a tire-mold assembly thereon comprising a lower mold section 11 and an upper mold section 12 which is formed on its inner periphery with apertured lifting lugs such as the lug 13.

Extending along the conveyor, above the same, is an endless overhead track 1 1 having an inclined reach 15 adapted to effect an ascent or descent of the suspension device in the travel of the latter along the track, the said device being suspended from any one of a series of depending hooks 16, 16, each of which hasits shank secured to the axle of a pair of rollers such as the roller 17 running upon the rails of the track, and the said rollers being in a series of pairs of rollers mounted upon the rails and having their axles connected by link members 18, 18 to provide an endless drive chain.

The suspension device is mounted upon a hook 16 by means of an eye-bolt 19 upon the depending shank of which is swiveled a yoke 20 having each of its arms joined by an eyelink 21 to the two juxtaposed shank portions of a metal strap 22 which is bent into an elongated U-shaped loop, the end or shank portions of the strap being bolted to the lower eye of the member 21.

A similarly bent metal strap 23, inverted, is interlinked with the strap 22 and a compression spring 24 interposed between the closed ends or spring-seating bases of the two loops urged each of the straps toward the attachment end of the other in a manner such that the spring resists elongation of their combined structure.

To limit the contraction of the structure under the force of the spring 24 a bridge plate 25 to be abutted by the loop base of the strap 23 is mounted between the legs of the strap 22 and is formed with tenons 26, 26 extending through slots in the said legs and a similar bridge plate 27 adapted to be abutted by the loop base of the strap 22 is mounted between the legs of the strap 23 and formed with tenons such as the tenons 28, 28 (Fig. 1) extending through slots formed in the legs. The spring is of such length and the bridge plates are so positioned as to hold the spring under suitable compression to support a heavy load without much further shortening of the spring.

To hold the interlooped straps in alignment while permitting them to slide with relation to each other in the extension and contraction of the device and to serve as a spring post a guide rod 29 extends through the spring and through central guide-apertures formed in the bridge plates and in the loop bases of the straps, and to retain the guide rod in the assembly it is provided at each of its ends with a cotter pin. 8.0-.

Tolimit the elongation of the structure a length of pipe 31, surrounding the spring 24 and requiring no fixed attachment, is interposed bet-ween the loop bases of the straps, the

pipe length being suflici'ently short to provide a suitable range of elongation andcontraction of the structure and the guide rod 29 being of such length between. its cotter pins as not to subject the latter to load in contact with the respective bridge plates 25, 27.

Mounted between the lower ends of the strap 23' and bolted and doweled thereto is a mold-engaging hook 32, the two hooks 32 of the complete assembly being adapted to be engaged in the respective apertured lugs 13 of the upper mold section 12.

In the operation of, the particular apparatushere shown, the drive chain of the overhead track, having thereon a spaced succession of depending hooks as described, is driven at the same horizontal speed as that of the mold conveyor and mold assemblies are mounted upon the conveyor in spaced relation at one end of its orbit. lVhile the hooks 16 are at a low part of the overhead track, a suspension assembly is su'pen'de'd from a hook which is above a, mold assembly, eachmember of the suspension assembly being free and consequently contracted to the limit imposed by the bridge plates 25-, 27, the operator engaging the hooks 32 with the respective lugs 13 of the upper section 12. of said mold assembly, any necessary lowering of the first engaged hook 32 being permitted by tilting of the assembly upon the hook 16 and loweringof the other hook 32then being permitted by the extensibility of the interlooped strap assembly.

As the suspension device assembly then moves upward on the next inclined portion ofthe overhead track it lifts the mold section 12, thus opening the mold for the removal of the tireand the insertion of another tire in the mold for the next vulc'anizing operation.

At a suitableposition in the system: decline isprovi'ded in -the overhead track and at that point the mold, is closed upon the substituted tire and the suspension device as sembly is disengaged from the upper mold section and from the hook 16 by a reversal of the steps just described.

The severalparts of the suspension assembly are" easyand inexpensive to manufacture and although they may readily be assembled and disassembled they provide a very sturdy an d durable structure- An; important advantage inherent in my suspension: device lies in the positioning of the spring within the loops of the interlinked members, so that the latter protect the hands of workmen from being pinched by the spring, which would frequently occur if the compression spring member were in an exposed position where it would be grasped by the workmens hands in the ordinary use of the suspension device.

Modifications are possible within the scope of my invention as defined in' the appended claims.

I claim:

1. A suspension device comprising a pair of metal members of open loop form interlinked with each other, a helical compression spring having its ends seated against the innor faces of the loop-ends of the respective members so. as to be opposed to elongation of their combined structure, a bridge member connecting the legs of one of the said members and a guide member interposed operatively betwen the said bridge member and the other looped member.

2. A suspension device comprising a pair of one-piece metal members of open loop form interlinked with each other, a compression spring interposed between and seated against their loop ends, and a bridge member connecting the legs of one of the said members and constituting a stop against extension of the spring.

3.. A suspension device comprising a pair of metal members of loop form interlinked with each other, a compression spring interposed between their loop ends, a bridge member on each of the said members and connecting its legs at a position spaced from their ends, and a guide bar. extending through the spring and engaging thesaid loop ends and the said bridge members.

4.. A suspension device comprising a pair of metal members of loop form interlinked with. each other, a compression spring interposed between their loop ends, a bridge member on each of the said members and connecting its legs at a position spaced from their ends, a guide bar extending through. the spring and engaging the said loop ends and the said bridge. members, and. a loose hollow member extending about. the spring and adapted to be abutted by the said loop ends to limit extension of the structure.

In witness whereof I have. hereunto set my hand this 10th day of November, 1927.

GEORGE, E. HOVVEY. 

